Message storage



p 1963 P. F. T. c. STILLWELL 3,403,390

MESSAGE STORAGE Filed Jan. 31, 1964 2 Sheets-Sheet l MESSAGE MATRIX FIG I MESSAGE. l

MESSAGE. Z l

MESSAGE STORAGE 2 Sheets-Sheet 2 Filed Jan. 31, 1964 United States Patent "ice 3,403,390 MESSAGE STORAGE Peter Frederic Thomas Cryer Stillwell, Aldershot, England, assignor to Rank-Bush Murphy Limited, London, England, a British company Filed Jan. 31, 1964, Ser. No. 341,790 Claims priority, application Great Britain, Feb. 1, 1963, 4,254/63 1 Claim. (Cl. 340-324) This invention relates to message storage arrangements.

It is sometimes useful to be able to store fixed data permanently so that it can be called up on demand in a random fashion. One example of this is a character generator where the shapes of symbols can be stored in terms of electrical components. If it is desired to provide a display of some of a number of symbols which together form fixed messages, it is uneconomic to store character shape as part of the message and a preferable method is to store a font of characters together with groups of codes which specify the desired characters in a message. A number of methods are available for storing a sequence of codes but most of them depend upon cores or magnetic elements because they have in general been developed for high speed computing applications. In a display, or a printer using a cathode ray tube, it is often desirable to have the code representing a character available for the whole period for which it is valid.

According to the present invention, a message storage arrangement is provided which comprises a store having a plurality of resistor elements arranged in a resistance matrix, the resistor elements forming connections between two groups of conductors of the matrix, sequential pulse generator means being provided for applying pulses sequentially to conductors of one group whereby output pulses are provided at individual conductors of the other group, the output pulses, for each sequential pulse of the generator means, being determined by the coded allocation of the resistor elements to that conductor of the said one group which corresponds to the respective sequential pulse.

One message out of many may be selected and the character signals emerge in parallel in a block of a plurality of amplifiers. The operation of the storage means may be extended, such as by time sharing or switching between blocks of amplifiers, to select a number of messages, for example ten messages, from a larger number of messages.

From a different aspect, a message storage and display arrangement according to the invention comprises a store having a plurality of resistance matrices formed by resistor elements connected between individual conductors of one group of conductors common to all the matrices and individual conductors of further groups of conductors which form the respective matrices in conjunction with the common group, sequential pulse generator means being provided for applying pulses sequentially to the conductors of the said one group, means being provided for rendering a selected one of said matrices effective for delivering groups of output pulses in codings corresponding to the allocation of resistor elements to the individual conductors of the said one group therein, said rendering means comprising means for successively sampling message selection input conductors to the arrangement whereby to sense energisation thereon, a character waveform generator being provided, the character waveform generator being arranged for supplying display character waveforms to a cathode ray tube for display of said characters, in correlation to the coding inherent in the groups of output pulses.

Embodiments of message storage means according to the present invention will now be described by way of Patented Sept. 24, 1968 example with reference to the accompanying drawings, in which:

FIGURE 1 represents, in block diagram form, an embodiment of message storage means; and

FIGURE 2 is a block diagram illustrating an application of the message storage means.

Referring to FIGURE 1 of the drawings, a sequential pulse generator, that is to say a unit which produces a pulse of voltage on one of a number of wires and where in response to an input clock pulse the pulse propagates to the next adjacent wire, generally indicated by the reference numeral 11, has a number of outlet wires 12 which form the vertical wires in a matrix. The horizontal wires 13 in the matrix are in groups of sixeach group representing the necessary wires for defining a single message. Resistance elements 14 are connected between the vertical wires 12 and the horizontal message wires 13 so that the position of these resistors 14 defines a code across the six horizontal wires 13. As shown, a resistance 14 is connected if a 1 is desired in the code and no resistance is connected if a zero is desired. The message wires 13 are all connected through diodes '15 to a set of six output amplifiers 16. Other diodes 17 are connected from all the wires 13 in a message array to a common wire called the message wire 18. The output amplifiers 16 are designed to have very low input impedance so that their input voltage does not change significantly in response to an input current.

It will be appreciated that if only one message wire '18 is positive with respect to the input potential of the amplifiers and the sequential pulse generator 11 is run, then a sequence of codes will appear at the output of the amplifiers '16 corresponding to the pattern set by the resistors 14 connected to that set of message wires. Moreover, if desired the sequential pulse generator may be stopped so that a single code is retained indefinitely.

Such a store is capable of being made quite cheaply. The sequential pulse generator 11 can be a decatron circuit designed to run at up to 50 kc./s. The resistances 14 themselves need not be accurate since only their presence or absence is of importance, and they could in fact be deposited metal films which are open circuited where desired. Each message requires twelve diodes and an average of three resistors per code, and the sequential pulse generator 11 and output amplifiers 16 are common to the store.

The scheme can be extended to include a parity track if desired and failure of parity could be arranged to display a special symbol.

FIG. 2 shows an arrangement for use in aircraft or elsewhere which uses the message store shown in FIG. 1.

The purpose of this circuit is to enable the continuous display of any selected messages on a cathode-ray tube, so that, for instance in response to a fault or faults occuring in a complex system and signalled upon a single wire, the necessary remedial actions can be displayed in plain language on a centrally located cathode ray tube. The application, although originally conceived for aircraft, can be applied to any system in which an operator has to scan a very large number of instruments and take action when a fault occurs.

In FIG. 2, the message store shown in FIG. 1, is indicated by block 22 and may contain a great number of stored fixed messages. The message select Wires, which correspond to the Wires 18 of FIG. 1, enter the message store through and gates 23, and the gated select wires are all taken to an or gate 24. A selection sequential pulse generator or shift register 25 is arranged so that a voltage appears on only one of its outputs each of its outputs being connected to one of the input select gates. The single output voltage can be cycled around all the input connections under the control of an oscillator '26 conditioned by an and gate 27 controlled by a bistable element 28.

When gate 27 is allowed by bistable element 28, the oscillator 26 causes an output voltage to appear rapidly and successively on each of the outputs of the sequential pulse generator 25, so that all the message select wires are sampled successively. This process continues until an energized select" wire is sampled. This is detected by or" gate 24 and the output from the or gate 24 switches the bistable element 28 thereby disconnecting the oscillator 26 from the sequential pulse generator or selection register 25. At the same time the output from the or gate 24 opens gate 31 and allows an output from oscillator 29 to enter a message selection sequential pulse generator 30 and thus read out the stored codes successively. These codes are fed to a character waveform generator 34 which generates X and Y deflection waveforms from a cathode ray tube (not shown) so as to draw a character. It will be appreciated that a character generator of this form is not required if a shaped-beam tube is used for the display.

A horizontal scan waveform to position the characters on the cathode ray tube may be generated in a generator 32 by using the output of the gate 31 to generate a step waveform which is then returned to zero by the end of message output from the sequential pulse generator 30. Similiarly, a vertical position waveform may be generated by using the end of message waveform to generate a step waveform and the end of cycle output the sequential pulse generator 25 to return the step waveform to zero. These waveforms are then added in units 35 to provide X and Y deflection waveforms.

The system described above is capable of displaying a number of messages on a single cathode ray tube and the messages are selected by single wires. Moreover the messages can be displayed in tabular form and the wiring can be arranged so that the most important message appears at the top of the tables.

It will be appreciated that in certain systems it may be desirable to display a fixed line of data followed by certain variable data (for instance where it is desirable to indicate a temperature at some point in a plant). In these applications the arrangement of FIG. 2 is suitable and the desired result can be obtained by extending the message sequential pulse generator 30 so that after all the fixed codes have been read a number of further codes presented on a set of input staticisors by the source of variable information are presented to the character waveform generator 34 and after this the message end signal is generated. This is enabled by the arrangement of FIG. 2, in which the codes from the message store 22 pass through the gates 37 which also have inputs from staticisors 38. A variable data sequential pulse generator 36 which is constituted by the above mentioned extension of the message sequential pulse generator 30 generates a number of pulses the first of which serves to allow the outputs of staticisors 38 to enter the character waveform generator 34 via gates 37 after the codes representing the fixed message have been displayed. Subsequently, pulses from the variable data sequential pulse generator 36 select further data from a variable data store (not shown) connected to the staticisors 38 and read out the variable information. After the variable data sequential pulse generator 36 has completed the number of pulses which are allowed for variable data, the message end signal is generated.

It will be appreciated that although one set of input staticisors 38 may be used for variable data, this actual data must be associated with the appropriate fixed message. This can be arranged by using the output from the message selection sequential pulse generator 30 to connect the appropriate source of variable data to the variable data staticisors 38.

I claim:

1. A message storage arrangement comprising,

a first and second plurality of conductors in a matrix array, said second plurality of conductors being arranged in predetermined groups of conductors, each group having a common selector conductor,

storage means having a plurality of resistor elements arranged in a resistance matrix, said resistor elements selectively forming connections between said first and second plurality of conductors,

sequential pulse generator means for sequentially applying pulses to said first plurality of conductors, whereby output pulses appear at individual ones of said second plurality of said conductors, each of said output pulses being determined by the coded allocation of the resistor elements to that conductor of the first plurality of conductors which corresponds to the respective sequential pulse,

means for selecting said predetermined groups of conductors from which said output pulses appear by selectively enabling said common group selector conductors, wherein each of said second plurality of groups of conductors are connected to the same set of individual amplifiers by means of diodes, the individual conductors of said groups being connected through diodes to said common group selector conductors, the arrangement being such that selection of the group of conductors from which output pulses are provided can be effected by suitably biasing the corresponding common group selector conductor,

display means for displaying characters forming a message or part thereof, said characters or some of the displayed characters being allocated to sequential groups of output pulses, wherein said display means comprises a character waveform generator providing beam deflection potentials for a cathode ray tube on which the characters are to be displayed, the generated waveforms being correlated to the respective groups of output pulses, and

means for controlling the character waveform generator for the generation of characters representative of variable data in addition to the generation of characters representative of the selected stored message.

References Cited UNITED STATES PATENTS 3,047,851 7/1962 Palmeter 340324.1 3,104,387 9/1963 Loshin 340324.l 3,165,729 1/1965 Richman IMO-324.1 3,205,488 9/1965 Lumpkin 340324.l 3,234,534 2/1966 Todman 340324.1 3,248,725 4/1966 LOW et al. 340-324.l 3,296,609 1/1967 Wilhelmsen 340324.1 3,329,947 7/1967 HarrOwe et a1. 340-3241 3,329,948 7/1967 Halsted 340324.1

JOHN W. CALDWELL, Primary Examiner.

A. J. KASPER, Assistant Examiner. 

1. A MESSAGE STORAGE ARRANGEMENT COMPRISING, A FIRST AND SECOND PLURALITY OF CONDUCTORS IN A MATRIX ARRAY, SAID SECOND PLURALITY OF CONDUCTORS BEING ARRANGED IN PREDETERMINED GROUPS OF CONDUCTORS, EACH GROUP HAVING A COMMOM SELECTOR CONDUCTOR, STORAGE MEANS HAVING A PLURALITY, OF RESISTOR ELEMENTS ARRANGED IN A RESISTANCE MATRIX, SAID RESISTOR ELEMENTS SELECTIVELY FORMING CONNECTIONS BETWEEN SAID FIRST AND SECOND PLURALITY OF CONDUCTORS, SEQUENTIAL PULSE GENERATOR MEANS FOR SEQUENTIALLY APPLYING PULSES TO SAID FIRST PLURALITY OF CONDUCTORS, WHEREBY OUTPUT PULSES APPEAR AT INDIVIDUAL ONES OF SAID SECOND PLURALITY OF SAID CONDUCTORS, EACH OF SAID OUTPUT PULSES BEING DETERMINED BY THE CODED ALLOCATION OF THE RESISTOR ELEMENTS TO THAT CONDUCTOR OF THE FIRST PLURALITY OF CONDUCTORS WHICH CORRESPONDS TO THE RESPECTIVE SEQUENTIAL PULSE, MEANS FOR SELECTING SAID PREDETERMINED GROUPS OF CONDUCTORS FRO WHICH SAID OUTPUT PULSES APPEAR BY SELECTIVELY ENABLING SAID COMMON GROUP SELECTOR CONDUCTORS, WHEREIN EACH OF SAID SECOND PLURALITY OF GROUPS OF CONDUCTORS ARE CONNECTED TO THE SAME SET OF INDIVIDUAL AMPLIFIERS BY MEANS OF DIODES, THE INDIVIDUAL CONDUCTORS OF SAID GROUPS BEING CONNECTED THROUGH DIODES TO SAID COMMON GROUP SELECTOR CONDUCTORS, THE ARRANGEMENT BEING SUCH THAT SELECTION OF THE GROUP OF CONDUCTORS FROM WHICH OUTPUT PULSES ARE PROVIDED CAN BE EFFECTED BY SUITABLY BIASING THE CORRESPONDING COMMON GROUP SELECTOR CONDUCTOR, DISPLAY MEANS FOR DISPLAYING CHARACTERS FORMING A MESSAGE OR PART THEREOF, SAID CHARACTER OR SOME OF THE DISPLAYED CHARACTERS BEING ALLOCATED TO SEQUENTIAL GROUPS OF OUTPUT PULSES, WHEREIN SAID DISPLAY MEANS COMPRISES A CHARACTER WAVEFORM GENERATOR PROVIDING BEAM DEFLECTION POTENTIALS FOR A CATHODE RAY TUBE ON WHICH THE CHARACTERS ARE TO BE DISPLAYED, THE GENERATED WAVEFORMS BEING CORRELATED TO THE RESPECTIVE GROUPS OF OUTPUT PULSES, AND MEANS FOR CONTROLLING THE CHARACTER WAVEFORM GENERATOR FOR THE GENERATION OF CHARACTERS REPRESENTATIVE OF VARIABLE DATA IN ADDITION TO THE GENERATION OF CHARACTERS REPRESENTATIVE OF THE SELECTED STORED MESSAGE. 